1,4,Bis-N,N&#39;-dipolyalkylquinonyl aminopropyl piperazine

ABSTRACT

Ortho-quinones with alkyl, olefin polymer, or halogen substituents and a process for the preparation of these compounds comprising a base catalyzed halogen oxidation of alkylated phenol.

This is a division of application Ser. No. 062,333, filed July 31, 1979,now U.S. Pat. No. 4,362,668, which is a division of Ser. No. 955,930,filed Oct. 30, 1978, now U.S. Pat. No. 4,208,340.

This invention relates to substituted ortho-quinone compounds. Moreparticularly this invention relates to ortho-quinones with alkyl, olefinpolymer, or halogen substituents, and to a process for the preparationof these compounds wherein alkylated phenol is oxidized by a halogencompound in the presence of a base catalyst.

Ortho-quinones are useful as intermediates in the production of severaltypes of compounds such as antioxidants, rust inhibitors, insecticides,fungicides, and ultraviolet absorbers. Substituted ortho-quinonestraditionally have been generated by the introduction of oxygen into asuitably substituted phenol or by the oxidation of catechol derivatives.For example, the oxidation of chlorinated catechols to prepare mono- anddichlorinated ortho-quinones is disclosed by Willstatter, Chem. Ber.,44, 2182, 1911. Several different substituted phenols have been oxidizedto ortho-quinones by the alkali salts of nitrosodisulphonate. Teuber andStaiger, Chem. Ber. 88, 802, 1955. An extensive review of the synthesisand thermal reactions of ortho-quinones covering the years 1947-1967 hasbeen made by W. M. Horspool. Quarterly Reviews, No. 2, Vol. 23, p. 204,1969. Both the introduction of oxygen into phenols and the oxidation ofcatechol derivatives are thoroughly discussed and referenced. Gess andDence in Tappi, 54(7), 1114-21, 1971 discuss the preparation ofchloromethylortho-quinones from creosol through chlorination withsubsequent cleaving of the ether linkage of the methoxy substituent. Thepreparation of completely dehydrogenated quinones is disclosed in U.S.Pat. No. 3,479,374. The class of alkylated ortho-quinones of the presentinvention however has not been disclosed because the traditionaloxidation methods are not desirable for generating these novelcompounds. Previously known oxidation methods, especially thoseinvolving acid catalysis, tend to cause dealkylation of aliphaticsubstituents of about twelve or more carbon atoms during the oxidationprocess. A need exists for ortho-quinone compounds with substituents ofthis size and for a process for their preparation because of the largenumber of useful derivatives that can be generated from them.

The object of this invention is to provide a new class of ortho-quinonecompounds. A further object is to provide a halogen oxidation processfor the preparation of these quinone compounds. Another object is toprovide useful quinone intermediates for the generation of several typesof derivative compounds. Other objects appear hereinafter.

We have found that it is possible to produce a new class of substitutedortho-quinone compounds comprising alkylated ortho-quinones andalkylated halogenated ortho-quinones by a base catalyzed halogenoxidation of an alkylated phenol. As indicated above, theseortho-quinone compounds are useful intermediates in the production ofanti-oxidants, rust inhibitors, insecticides, fungicides, andultraviolet absorbers.

The compounds of the present invention are substituted ortho-quinoneshaving the structure: ##STR1## wherein R is an aliphatic chain,preferably a hydrocarbyl chain of at least 12 carbon atoms, such as aC₁₂ or higher branched or straight chained alkyl or a C₃ or higherolefin polymer with M_(n) of about 170 to about 2100; and X is hydrogenor halogen such as, chlorine, bromine, or iodine. Preferably when R is apolymer substituent it comprises a tetramer or higher homolog ofpolypropylene or polybutene. The halogen group, when present, rendersthe ortho-quinone more reactive since the compound is then capable offacile substitutions by virtue of the labile halide function. Thehalogenated ortho-quinones are therefore especially useful in generatingderivatives containing the corresponding alkyl or polymer substituent.

The alkylated ortho-quinone compounds can be produced by the oxidationof a monoalkylated meta or paraphenol by a halogen compound in thepresence of a base catalyst. This method of oxidation is also a means ofhalogenation to obtain the halogenated alkylated orthoquinone compounds.The reaction is believed to be an ionic one via a phenate ion mechanismrather than a free radical reaction because the aliphatic substituent onthe phenol reactant remains intact on the ortho-quinone generated. Thispermits selectivity in the generation of a quinone intermediate for aspecific derivative application.

Alkylated phenols suitable as reactants include meta or paraphenolswherein the substituent comprises an aliphatic chain, preferably ahydrocarbyl chain of at least 12 carbon atoms, such as a C₁₂ or higherstraight chained or branched alkyl group like dodecyl, tridecyl,tetradecyl, pentadecyl, octadecyl and similar groups, or a C₃ or higherolefin polymer of M_(n) from about 170 to about 2100 such as a tetrameror higher homolog of polypropylene or polybutene. Preferred areparaphenols with substituents of polypropylenes of M_(n) of about 170 to800 or polybutenes of M_(n) of about 225 to 2100. These polymers areusually generated from refinery streams by polymerization in thepresence of a suitable catalyst such as aluminum chloride. Processes forthe alkylation of phenols to generate the desired reactants are widelyknown. See U.S. Pat. Nos. 2,398,253; 2,655,544; 2,671,117; and BritishPat. No. 1,159,368.

Because of their high viscosities the polymer substituted phenols arecommonly diluted in an oil solvent to enable easy transport andhandling. The amount of solvent varies widely. Commonly the diluent isused in such concentrations that achieve a suitable viscosity for thereaction mixture or product for ease of reaction and transfer while notunnecessarily diluting the final product. Suitable solvents includemineral lubricating oils of grades from light white oils to SAE-40. Thediluent oils can be solvent extracted to avoid the presence of additivesor impurities. SAE-5W is preferred as a diluent for the phenols used inthe oxidation reaction.

Halogens appropriate to effect the oxidation include chlorine, bromine,and iodine. A molar amount of halogen that is equal to or exceeds themolar amount of phenol reactant is preferred. The halogen is added tothe reaction mixture in elemental form as a gas at a rate of about200-400 cc per minute (approximately 9-18 moles per minute until noadditional absorption occurs. Chlorine is preferred for the reactionbecause it is less expensive than the other halogens. In themanufacturing facility excess unreacted halogen could be recovered,separated from air, and recycled.

Suitable solvents for the reaction include inert hydrocarbons such asbenzene, toluene, xylene or halogenated benzenes such as chlorobenzene,dichlorobenzene, and similar compounds. The particular solvent chosen isbased on the temperature range desired for the reaction since thereaction is preferably carried out under refluxing conditions. An inertsolvent such as benzene is preferred.

The halogen oxidation is a base catalyzed reaction. Catalystsappropriate include metallic hydroxide compounds such as lithiumhydroxide, sodium hydroxide, potassium hydroxide, magnesium hydroxide,and calcium hydroxide. Sodium hydroxide is preferred for economicreasons. The catalyst is usually added to the reaction mixture in solidform.

In somewhat greater detail the alkylated orthoquinones are generated byoxidation of a monoalkylated phenol in a suitable solvent by theaddition of a halogen compound as a gas in the presence of a basecatalyst. The reaction can be carried out at atmospheric pressure attemperatures from 0° to 200° C., preferably at the refluxing temperatureof the solvent. After completion of the reaction, the solvent can beseparated by distillation of the reaction mixture and precipitatedbyproducts by filtration or other appropriate means of separating solidsand liquids. The resulting quinone solution can then be concentrated bynitrogen sparging or equivalent means. The aliphatic substituent on thephenol reactant remains intact on the ortho-quinone generated.

To effect the oxidation reaction for generating ortho-quinones thealkylated phenol, an appropriate solvent such as benzene, and the basecatalyst, preferably sodium hydroxide in solid form, are introduced intoa conventional reaction vessel. The halogen gas, preferably chlorine, isintroduced through a dispersion tube into the bottom of the reactionmixture at a rate of about 200 cc to 400 cc per minute (approximately9-18 moles per minute). The amount of catalyst and halogen preferablyeach exceed the amount of phenol. Mole ratios of 1:1 to 6:1 catalyst tophenol and of 1:1 to 20:1 halogen to phenol can be used. Uponintroduction of the halogen, heat is applied to the system with stirringto aid in generating contact and initiating the reaction.

The reaction can be carried out at temperatures of 0° C. to 200° C.,preferably at the refluxing temperature of the solvent employed. Therefluxing temperature is used as a means of controlling the reaction.Use of a lower temperature results in the disadvantage of a reducedreaction rate and longer reaction time while at higher temperatures theoxidation can be difficult to control. At the refluxing temperature thereaction can be conducted at atmospheric pressure.

The oxidation can be considered complete when the pH of the reactionmixture becomes acidic as demonstrated by a litmus test and freechlorine, no longer absorbed by the system, is emitted from the exhaustof the reactor. The reaction mixture is usually distilled to separatethe solvent, yielding an azeotrope of solvent and water. Precipitatedsalt byproducts, such as metallic chlorides and bleach powder, can beremoved by filtration or other equivalent means. The filtrate can thenbe concentrated by sparging with nitrogen or other inert gas up to 200°C. to yield the desired substituted ortho-quinone.

The halogenated ortho-quinone derivative can be generated eitherdirectly from the oxidation of the alkylated phenol or by halogenationof the alkylated ortho-quinone produced from the phenol oxidation. Inthe oxidation reaction a mole ratio of halogen to phenol of about 9 to 1is normally used to produce ortho-quinone and of about 18 to 1 toproduce halogenated ortho-quinone. All other reaction conditions andseparation techniques required remain the same as previously described.To generate the halogenated ortho-quinone derivative from thecorresponding alkylated ortho-quinone, standard methods of halogenationcan be utilized or alternately the ortho-quinone can be treated in amanner analogous to the phenol in the oxidation reaction. This two stepmethod permits use of a less expensive halogen to generate the quinoneand substitution of a desired halogen in the later halogenationreaction.

Yields of 50-95% quinone as measured by activities can be obtained usingthis process. The aliphatic substituent on the phenol reactant remainsintact on the ortho-quinone generated. The phenol reactant therefore canbe selected in accordance with the substituent desired on theortho-quinone since no substantial change in the substituent occursduring the oxidation. Since ortho-quinones are used as intermediates togenerate a wide variety of derivatives this attribute is an advantage inthat it permits generation of the exact intermediate desired for aspecific application.

One type of derivative which can be generated is dipolyolefin quinonecompounds. This can be accomplished by adding polyalkylortho-quinone inacetic acid to a solution of potassium dichromate, manganese acetate,and water to effect an oxidative coupling reaction. The reaction can beused as a means of increasing the molecular weight of polymerscontaining an ortho-quinone. The dipolyalkylortho-quinones generatedhave the following structure: ##STR2## These compounds can be used asultraviolet absorbers, insecticides, and intermediates for oxidationinhibitors.

A second type of derivative that can be generated frompolyalkylortho-quinone is piperazine compounds useful as dispersantswith special antioxidant properties. This can be accomplished by addingbis-aminopropylpiperazine dropwise to a solution of monohalogenatedpolyalkylortho-quinone and then refluxing. Calcium hydroxide can beadded to precipitate out chloride byproducts. Upon separation andconcentration 1,4-bis, N,N'-dipolyalkylquinonyl aminopropyl piperazineis obtained. This compound has the following structure: ##STR3## Spotdispersancy tests and varnish tests for oxidation have shown thiscompound to possess both dispersancy and antioxidant properties.

A class of antioxidants that can be produced fromhaloalkylortho-quinones is represented by the metallic dithiophosphonatederivative, such as zinc dithiophosphonate. This derivative can be madeby first reacting haloalkylortho-quinone with phosphorus pentasulfide inan inert gas atmosphere and then after solvent removal adding a metallicnitrate slurry in oil to the reaction mixture. The resulting product isbelieved to be the following: ##STR4## X=halogen M=bivalent metal

An oxidation inhibitor derivative can be generated by the reaction ofhaloalkylortho-quinone with sulfur monochloride. The product generatedhas the following structure: ##STR5##

The condensation of alkylortho-quinones yields a compound which meetsthe structural demands of known compounds used as color preservatives inplastics. This product can be generated by reacting alkylortho-quinonewith aluminum chloride in nitrobenzene. Upon chromatographic separationthe condensation product obtained has the following structure: ##STR6##

Another type of antioxidant can be generated by reactingalkylortho-quinone with ammonium acetate and paraformaldehyde underpressure. The product is an alkylated aza indene derivative with amolecular weight of about 570 with the following structure: ##STR7##

These are representative of the wide variety of derivatives that can begenerated from the substituted quinone compounds of the presentinvention.

EXAMPLE 1

Approximately four moles of paradodecylphenol (1000 g) were dissolved inone liter of benzene in a reaction vessel equipped with a condenser andstirring device. Seven and one half moles (300 g) of solid sodiumhydroxide were added. Chlorine gas was introduced at a rate of 200 ccper minute (approximately 9 moles per minute) throughout the reaction.Excess unreacted chlorine was not recovered for recycle. The reactionmixture was refluxed at approximately 80° C. for seven hours. Uponcompletion of the oxidation the reaction mixture was acidic as measuredby a litmus test and free chlorine, no longer absorbed by the system,was emitted from the exhaust of the reactor. Distillation of thereaction solution gave an azeotrope of water and solvent. Sodiumchloride and sodium hypochlorite precipitated and were removed byfiltration. The quinone solution was concentrated by nitrogen spargingup to 150° C. yielding a dark red viscous liquid. Infrared analysis wasperformed upon a sample of the product and showed quinone and conjugatedcarboxyl absorption bands with no hydroxy absorptions and little or noaromatic substitution bands. The dodecylortho-quinone generated wasdissolved in benzene, sodium hydroxide added, and the reaction mixturetreated with chlorine gas at 400 cc per minute with refluxing as above.Separation and concentration of the reaction product as above yieldedchlorododecylortho-quinone. Elemental analysis of themonochlorododecylortho-quinone for chlorine showed 11.5% presentcompared to a theoretical value of 11.3%. Chromatographic analysis gave95% yield of quinone.

This example illustrates the production of dodecylortho-quinone andchlorododecylortho-quinone through chloro-oxidation of paradodecylphenolin the presence of a base catalyst. Dodecylortho-quinone andchlorododecylortho-quinone were also generated using a lower mole ratioof sodium hydroxide to dodecylphenol. Data is summarized in Table I.

                  TABLE I                                                         ______________________________________                                        Example      1a       1b       1c     1d                                      ______________________________________                                        Moles Dodecylphenol                                                                         4        4        4      4                                      Moles NaOH   7.5      7.5      7.5    5                                       Solvent      Benzene  Benzene  Benzene                                                                              Benzene                                 Temp. °C.                                                                           80       80       80     80                                      Yield of Quinone                                                                            95%      71%      65%    66%                                    ______________________________________                                    

EXAMPLE 2

This example illustrates the production of polybutylortho-quinone andchloropolybutylortho-quinone using the method of Example 1. One halfmole of parapolybutylphenol (M_(n) 1600) in 50% 5W oil was dissolved inone liter of toluene in a conventional glass reactor equipped as inExample 1. Three moles (120 g) of solid sodium hydroxide were added tothe solution and chlorine gas introduced at a rate of 200 cc per minute(approximately 9 moles per minute). The reaction mixture was refluxed attemperatures of 95°-125° C. for five to seven hours. At the completionof the oxidation the reaction mixture was acidic as measured by a litmustest and free chlorine, no longer absorbed by the system, was emittedfrom the exhaust of the reactor. The desired polybutylortho-quinone wasseparated as in Example 1 and identified by infrared spectroscopy.Chloropolybutylortho-quinone was then generated as in Example 1.Elemental analysis for chlorine was performed to verify productidentification. Polybutylortho-quinone and chloropolybutylortho-quinonewere also generated using lower mole ratios of sodium hydroxide topolybutylphenol. Data is summarized in Table II.

                  TABLE II                                                        ______________________________________                                        Example      2a          2b       2c                                          ______________________________________                                        Moles Polybutylphenol                                                                      0.5         0.5      0.5                                         Moles NaOH   3.0         2.0      1.0                                         Solvent      Toluene     Benzene  Benzene                                     Temp. °C.                                                                           115         80       80                                          Yield of Quinone                                                                             90%       60%      53%                                         ______________________________________                                    

EXAMPLE 3

This example illustrates the production of di-polybutyl quinones by anoxidative coupling reaction. Polybutylortho-quinone was made accordingto the procedure of Example 2. One half mole (1385 g) ofpolybutylquinone in 5W oil was dissolved in acetic acid. This was addedslowly to a stirred solution of 88 g (0.3 mole) of potassium dichromate,30 g of manganese acetate, and 40 cc of water in a conventional glassreactor. The reaction mixture was heated and refluxed at approximately120° C. until the color turned green indicating oxidation had occurred.The product was washed to remove acid and salts. The average molecularweight of the product recovered was 3085 and its activity was 55%. Theproduct was identified by infrared spectroscopy. The dipolybutylquinones are useful as ultraviolet absorbers, insecticides, and asintermediates to generate oxidation inhibitors. In addition thisreaction process can be used to increase the molecular weight ofpolymers containing ortho-quinones.

EXAMPLE 4

This example illustrates the production of the derivative 1,4bis-N,N'-dipolybutylquinoyl aminopropylpiperazine. To the reactionmixture of Example 2 containing chloropolybutylortho-quinone afterremoval of water by azeotropic distillation 50 g (1/4 mole) ofbis-aminopropylpiperazine were added dropwise. The reaction mixture wasthen heated under reflux conditions at about 115° C. for one hour. Toremove chloride by-products 37 g of calcium hydroxide in 600 cc of 5Woil were added to the reaction mixture and the reaction was continuedfor an additional two hours. The mixture was filtered hot over celite toseparate the chlorides and concentrated by stripping with nitrogen.Elemental test for nitrogen showed 1.33% present compared to atheoretical amount of 1.63%. The compound had an activity of 45%. Thedispersancy and antioxidant properties of the compound were confirmed byanalytical testing. A spot dispersancy test result of 92 compared to astandard of 85 was obtained. In a hot tube varnish test for oxidation ascore of 8.5A on a scale where 10A is perfect was obtained.

EXAMPLE 5

This example illustrates production of the zinc dithiophosphonatederivative of chlorododecylortho-quinone. One and one half moles (490 g)of monochlorododecyl ortho-quinone from Example 1 were dissolved in 500ml of benzene and 300 g of phosphorus pentasulfide were added slowlyunder an atmospheric of nitrogen. The reaction mixture was refluxed atabout 80° C. and solvent then removed by distillation up to 120° C. andnitrogen purging. A slurry of 149 g of zinc nitrate in 250 ml of 5W oilwas added to the reaction mixture. The reaction was continued at 150° C.and again purged with nitrogen for one hour to remove nitrous fumes. Theproduct was separated by filtration over celite. A 60% conversion wasobtained. Elemental analysis showed the presence of 14.5% sulfur, 7.2%zinc, and 6.8% phosphorus. The corresponding theoretical values are14.6% sulfur, 7.4% zinc, and 7.1% phosphorus. This derivative is usefulas an antioxidant.

EXAMPLE 6

This example illustrates the reaction of substituted ortho-quinones withsulfur monochloride to generate dibenzo [c,f][1,2,5]trithiepin(1,10-dialkyl-2,9-dichloro-4,7 dihydroxy). Approximately one half mole(160 g) of chlorododecylortho-quinone from Example 1 was dissolved in300 ml of benzene and one mole (135 g) of sulfur monochloride was added.The reaction mixture was refluxed for four hours at about 80° C. andproduct was recovered by stripping the solvent with nitrogen andfiltering over celite. Elemental analysis of the product showed thepresence of 12.4% sulfur and 11.9% chlorine compared to theoreticalvalues of 14.0% for sulfur and 11.9% for chlorine. The product is usefulas an oxidation inhibitor.

EXAMPLE 7

This example illustrates the condensation of alkylated ortho-quinones.To 366 gm of dodecylortho-quinone prepared as in Example 1 in 100 ml ofnitrobenzene 66.5 g of anhydrous aluminum chloride were added. Thereaction was stirred for six hours at 65° C. A slow evolution ofhydrochloride gas occurred. After chromatographic separation a 10%product yield was obtained. The product was identified by infraredspectroscopy and was found to meet the structural demands of knowncompounds used as color preservatives in plastics.

EXAMPLE 8

This example illustrates the production of an alkylated aza indenederivative useful as an antioxidant. Forty grams of dodecylortho-quinoneprepared as in Example 1 was reacted with thirty grams of ammoniumacetate and ten grams of paraformaldehyde under 5 pounds of pressure at150° C. for 2 hours. The alkylated aza indene product was 99% active andhad a molecular weight of 568. The product was identified by infraredspectroscopy.

I claim:
 1. A bis-aminopropylpiperazine derivative of alkylatedortho-quinone having the structure: ##STR8## wherein R is an aliphatichydrocarbyl chain of at least 12 carbon atoms selected from the groupconsisting of an alkyl of at least 12 carbon atoms and a polymer of anolefin of at least 3 carbon atoms.